The present invention is directed to a centrifuge tube adapter or holder designated to carry a plurality of small volume tubes within a centrifuge rotor and, more particularly, is directed to a holder which permits the tubes to pivot from an inclined angle when the rotor is at rest to a horizontal orientation when the rotor is operational.
In certain clinical tests or experiments, it is desirable to place a large number of separate individual samples in a plurality of very small volume centrifuge tubes for placement in a specific centrifugation run to obtain the desired separation within the sample. Therefore, in order to provide the most efficient use of the centrifuge, it is desirable to place as many of these small volume tubes within a single centrifuge rotor as possible so that each centrifuge run is as efficient as possible. One approach is the placement of a plurality of small volume tubes within the rotor on some type of adapter to hold the tubes in a large rotor for centrifugation.
The problem with previous devices used to handle a plurality of small volume tubes related to the proper orientation of the tubes in the rotor after centrifugation. It is desirable not to have the tubes remain in a horizontal position once the centrifugation has been completed. Some previously designed holders that have been used to support small volume tubes did provide for the desired inclined rest angle, but did not provide the needed support to the upper end or collar of the tube to prevent extrusion of the tube during centrifugation. In other words, it is important that support is provided around as much of the upper end of the tube as possible. Unfortunately, the prior approaches have generally provided support to the collar of the swinging tube on two sides leaving over 180.degree. of the collar portion of the tube unsupported which results in possible deflection or deformity in the tube.
One prior art arrangement incorporates a flat thin plate that has elongated holes into a rotor with a plurality of radially extending sections or arms forming a plurality of yokes. Slots are formed in the opposing arms within a yoke area into which the flat thin plate is positioned. The elongated holes permit pivoting of the tubes, but there is no locating function by the plate of the collar of the tube. Therefore, quite often the collar has significantly less than 180.degree. of support which may cause extrusion of the tube around the collar during high speed centrifugation.
It is also extremely important during the operation of the centrifuge that the tubes be generally free to move between the horizontal and the inclined position depending upon the speed of the centrifuge. Otherwise, the tubes may become askew or caught in the improper position. One reason for problems in this area has been the lack of provision of a proper pivot edge in the holder upon which the tube can rotate or pivot as the centrifuge moves from the rest position to the full operational speed. Similarly, the pivot area is important with respect to the movement of the tube from the operational speed to the rest position.